Warp-knitting machine



Mamh W46. A. FQFIORENTINO WARP-KNITTING MACHINE Filed July 14, 1943 3Sheets-Sheet l We BY VHO'UJ m Gwtbzl/ ATTOR EYS March 1946. A. F.FIORENTINO WARP-KNITTING MACHINE e R Y t E O m m, M

March 5, 1946. 1 A. F. FIORENTINO WARP-KNITTING MACHINE Filed July 14,1943 3 Sheets-Sheet s Q I INVENTORI .H- F FAIou/WM Patented Mar. 5, 19462.395.807 wane-KNITTING momma Anthony N. J a

F. Florentlno, Teaneck, N. .L, asslgnor to Alfred Holman & Company,

West New York.

corporation of New Jersey Application July 14, 1943, Serial No. 494,59631 Clalmsa (CI. 66-86) This invention relates to warp-knitting machines,a well known class wherein numerous warp yarns are fed from one or moresupplies or reels and through one or more banks of yarn guides formanipulation into warp-knitting fabric by cooperation with needles andother conventional knitting instruments; a typical prior instance ofsuch a machine being the double tricot knitting machine shown in priorcopending application of this applicant, Serial No. 455,186, filedAugust 18, 1942.

In the warp-knitting machine of said prior application there is providedan arrangement for relieving the yarns, as they are manipulated, duringknitting cycle after cycle, from the greater part of burden of having tostart into rotation each yarn reel at that part of each cycle when feedis demanded by the action of the knitting instruments; this object beingattained by the use of a'power driving mechanism, with timed clutch, anda yarn pilot or guide rod which is resiliently supported but is causedto yield by the pull of the yarns traveling over it, such pilot or guiderod being connected through a shipper device to operate the drivingclutch and impose the driving force upon the reel. The reel is thuspowerrotated for a small arc of movement by the combined tension pull ofthe yarns and power drive, which movement is thereupon caused to ceaseas the reel advance supplies the needed yarn or causes yarn slack, byreason of which the pilot relaxes or terminates the clutch drive and onthe contrary operates or imposes the action of a brake to retard or stopthe rotation of the reel; both the driving clutch and the retardingbrake being frictional in character and comprising friction shoesbearing upon friction disks or drums with greater or less pressure,under the described control of the pilot.

Such prior mechanism, particularly in regard to the reel retarding orbraking action, in respect to which the mechanism may be considered ofutility irrespective of the power driving action on able. The manualattention or control during the Y the reel, possessed a certainobjection by reason of the gradual changes of operating conditionsduring the consumption of the yarns as drawn from an initially fullreel; the diameter of the body of yarn upon the reel graduallydecreasing from an initial or full diameter to a minimum depleted orempty diameter. During such progressive depletion of the yarn supply theradius of the yarn supply and therefore the leverage and effectivenessof the tangential pull of the yarn upon the reel tends progressively todecrease, and this naturally renders somewhat more and more diflicultthe. action in each knitting cycle of starting or accelerating eachfeeding rotation of the reel, whether turned by the pull of the yarnalone or by such pull supplemented by a power drive means such asdisclosed in said prior application. In other words, the cyclical needof starting reel rotation became gradually more difiicult, tending tointroduce irregularities in action and even variations in the fabricproduced. Not merely does the progressive reduction of yarn radius tendto increase relatively the inertia to be overcome in each shift of thereel, but obviously in successive cycles the angle of each rotation andthe speed thereof are proportionately greater, to the detriment ofuniformity. It is true that the depletion of yarn reduces the mass andinertia of the reel and contents, but this factor is outweighed by theother factors mentioned. These described drawbacks pertain to priorprevailing machines generally and to'said prior application as oneillustration thereof.

To overcome partially the recited conditions and recognized drawbacks, aprevailing plan has been the manual one of periodically decreasing thestress of the long tensioning springs which bear upwardly and supportthe yarn pilot rod, namely, by lowering little by little during theexhaustion of the yarn supply the lower, abutments of such tensioningsprings, shown in the prior application. Such gradual readjustment ofthe springs by hand causes a readjustment or lowering of the operativerange of oscillation of the yarn-tensioning pilot and thus in turncauses a change in the position of the brake-relaxing rocklever orshipper in a sense to actuate the relaxing of the brakes somewhatearlier and to a greater extent, in each cycle, thereby to facilitate aneasier rotating of the reel when the point arrives to supply the neededyarn. But such lowered range and angle of the pilot swing and thehaphazard nature of the control are objectiondepletion of the yarn,however, is inadequate to ensure uniformity in the product fabric, andthey give an irregular action, with occasional'variationsappearing inthe fabric. The flow of yarn from the pilot to the knitting pointgradually varies in angle, especially in relation to .the swinging armsthat carry the pilot, andthis changes the relations and cooperations ofthe elements.

The impairment of fabric uniformity may be further explained as follows.Each lowering of the tension spring abutments decreases their tensionand shifts or lowers the range of pilot action, by which result thebrake shoes progressively relax and so assist in the operations of thereel to supply the needed yarn throughcycle after cycle. But thelowering of the spring tension causes a lowered yarn tension, and thismakes itself felt by a gradually looser fabric as knitted from thenearly depleted yarn. This while appreciable is-not always apparent, butis accompanied by a looseness and sometimes fluttering of the yarnbetween the pilot rod and the knitting elements, and so is apt to causedefects in the fabric, and require stoppage of the machine.-

These prevailing drawbacks apply, in the case of machines having reelbraking means whether or not having reel driving means. The machine ofsaid prior application has such a warp reel power drive, whichisresponsive, as is the brake, to the swinging of the yarn tension rodor pilot; and in respect to this drive the importance also exists ofmaintaining uniformity of operation throughout the gradual exhaustion ofthe yarn. This general problem or drawback is what concerns the presentinvention, which is intended to afford a regularized and automaticcontrol of the yarn tension and supply throughout the varying conditionscaused by the decreasing diameter of the yarn supply on the reel.

The main object of the present invention is to afford a warp-knittingmachine: of improved reliability of action, especially in respect todrawbacks due to the described varying conditions during the consumptionof yarn from the supply reel. A particular object is to provideautomatic regulating means for modifying the control of the reel brakingmeans by which the braking action or friction thereof is progressivelydecreased or relaxed accompanying the gradual depletion of the yarnsupply on the reel, thereby practically offsetting the effect of thechange of conditions during the consumption of the yarnfrom the supplyreel. A further object is to provide practical mechanisms andconnections for carrying out such regulation in a simple and effectivemanner.

For these purposes the present invention may be described in one aspectas consisting in a warpknitting machine wherein is a brake shoe, or acooperating opposite pair thereof, movably mounted to apply retardingeffect upon a disk or drum connected with the yarn reel; and incombination therewith a mechanism for progressively reducing theretarding effect of such brake shoe during the gradual depletion of thesupply of yarn on the reel, thereby to ease progressively the effort andstrain imposed upon the action which occurs during each cycle ofaccelerating or starting the yarn and reel into motion; said mechanismcomprising a movable follower which is arranged to bear upon the supplyyarn on the reel and thus undergo progressive shifting movement from aninitial to a final position during depletion of the yarn, the brake shoemountings or operating connections comprising a device which is operableor adjustable to relax the braking pressure independently of thecyclical operation of the brake shoe, and a mechanical connection fromsaid follower to said device such that, with the progressive shift ofthe follower, the device is adjusted gradually to relax the brakingpressure and amount of retarding effect upon the yarn reel.

In the accompanying drawings,

Fig. 1 is a left end elevation view of an illustrative warp-knittingmachine of the type shown in said prior application and includingsufficient of the mechanism thereof for the disclosure of the novelfeatures of the present invention.

Fig. 2'- is a detail section view taken on the line 2 -2 of Fig. 2.

Fig. 2 is a left elevation, similar to Fig. 1, but showing a second formor embodiment of the invention.

Fig. 3 is a similar view showing a third form of the invention.

Fig. 4 is a similar view showing a fourth embodiment.

Referring first to the embodiment of the invention shown in Fig. 1 thebank of yarns 11 is shown to be flowing downwardly from the yarn supplyY carried on the reel or warp beam 9 adapted to rotate step by stepabout a reel shaft iii, in gear with which, for example as in said priorapplication, is a shaft ii carrying a friction disk or drum i2, whichmay be the brake disk of the apparatus. In order to apply brakingfriction to the disk l2 there is at least one, and preferably a pair ofopposite friction shoes l3, at the left side of the figure and I3 at theright side. The application of the friction shoes for brakin 'the drumand reel is provided by a pair of brake levers, or shoe levers i4 and H,at the left and right, swinging respectively about overhead pivots oraxles l5 and it, the hubs l6 and E6 of the levers engaging directly onthe axles.

This arrangement of friction shoes and brake imposing levers correspondsto the illustration in said prior application, the parts herein beinghowever shown in an upright posture for convenience of illustration. Inthe normal operation of the knitting machine it is necessary during eachcycle to relax relatively the braking pressure and friction, andsimilarly to said prior application this is herein provided as follows.The left and right shoe levers l4 and I4 respecand H which are ofdifferent lengths to cooperate with the friction relaxing meansillustrated as comprising a shipper device i8. This shipper is in theform of a rock lever, set upright between the lower swinging ends of theshoe levers and mounted upon an axle 19, so that when the shipper isrocked in one direction it thrusts apart the free ends of the shoelevers thus to relax the braking pressure thereof upon the disk 12.Further, as in said prior application, the axle l9 may be a longitudinalrockaxle extending the whole length of the machine and giving support topart of the yarn guiding means as follows. Thus, mounted on the roekaxlel9 are carrier arms 20 supporting at their outer or righthand ends alongitudinal guide rod 21 which constitutes the movable yarn guide rodor pilot adapted to swing floatingly under the pull of the yarn andother operative factors. Thus the yarn y is seen to pass from the supplyreel at the left side thereof, downwardly and around a fixed guide rod22, and thence rightwardly around the pilot rod 2! and downwardly againat a slant toward the knitting point; the drawings showing in full linesthe normal or fully elevated position of the pilot 2| and carrying arms20, when the yarn is not under raised tension, and in dotted lines alowered position thereof produced by the tension existing in the yarnsduring certain parts of each knitting cycle.

These movements of the pilot are spring-controlled by the followingadditional elements, which provide a predeterminable yam tension, as inthe prior application. On the rockaxle I9 is shown a rightwardlyextending rockarm 23 which is tively are formed with depending lowerends ll knitting of any given length of fabric; change of strain may beinjurious to the yarns and at the best involves changes in tension suchas to affect objectionably the action of the knitpressed upwardly by along spring 24 surrounding a guiding bar and anchored at its lower endby abutments as in said prior application. By this arrangement the longspring 24 takes the weight of the elements 23, 20 and 2| as well as thestress produced by the downward pull of the tension of the yarns uponthe pilot rod 2|, therebyto mainsponsor,

tain the yarn at the desired tension. Thereby,

when the demand for yarn in each cycle causes the resilient lowering ofthe pilot rod, this swin s downwardly the carrier 20 and rockarm 23,compressing the spring 24 until equilibrium is reached; and this actionat the same time causes the rocking of the rockaxle I9 and thereby theswinging of the shipper l8, in a clockwise direction, so as to apply apressure upon the lower ends of the shoe levers tending -to swingthemapart and thus relax the frictional braking of the scribed.

disk I2 and reel 9, and so facilitating the necessary slight rotation ofthe reel to feed in'each cycle the length of yarn needed therefor. Whilethe relaxing of the braking action is thus efiected, this is inopposition to the .brake applying force of a cross spring 21 shown asextending from the leftto the right brake lever and thus pulling theopposite brake shoes forcibly upon the brake disk; the mounting of thecross spring upon the right:

hand lever 14' being shown as adjustable, bya device or thumb screw 28,to predetermine the maximum braking force. These several parts and theircooperation follow substantially the disclosure in said priorapplication; it being observed that the motions of the pilot rod are notwholly r n I provides for the gradual reduction of the retard-' ingeflect or friction of the braking shoes, calculated nd desi ned to relaxthe normalfrictlon of the shoes upon the disk, during the gradualdepletion of the yarn, thus to materially oilset or substantiallyequalize the tendency to an increase of resistance to the starting ofrotation, and thus larg'eiy neutralize the objection de- For thesepurposes the present invention, in the form shown in Fig. 1,- providesthe following novel mechanism and operation. Bearingupon the warp yarnsupply Y is shown a. follower or roller 34 whichis carried at the freeend of a swinging arm 35 fulcrumed on an axle 'or. pivot 36 in suchmanner thatthe follower can swing inwardly from the peripherytowardthe'cen'ter of the reel as the yarn is used up, the initial'outwardposition being shown in full lines and the furthest inward position indotted lines. The

swinging movements of the follower arm 35 are utilized to afford thecontrol mentioned. for which purpose the mountings or the operatingconnections of the brake shoe levers l4 and I4 are provided with adevice that is operable or adjustable to relax the braking pressureindependently of the cyclical .operations of the brake shoes, as willnext be described. I

Continuing the description of Fig. 1, from the follower arm 35, itspivot'36 is shown as carrying a rockarm 31, extending at an upwardoutward slant, its free end being slotted for adjustment purposes, andthere being a link 38 from said free determined by the length of yarnused for each knittedcourse or cycle, but largely rather, by the yarnmanipulating motions of the knitting elements which at one point lap theyarns around the needles, and also by the cooperating motions of otherknitting elements so that during these phases of each cycle it isessential-to provide suitable means adapted effectively to maintain theyarns under a practically constant tension.

As already described, as a given supply Y of warn yarns, initiallyfilling the reel 9, becomes used up, the changes in condition presentthe problem already described, name that progressively the force growsgreater that is needed tov produce each new short rotary advancemovement of the reel and yarn. If the pull of the yarns be the onlymeans for causing such intermittent turns of the reel and the yarnsupply then obviously, with the depletion of the yarn supply the strainand tension upon the yarns, thus applied during a short extent of eachknitting cycle, must gradually increase, as the supply is used up, thusunavoidably introducing irregularities and a decided lack of uniformityin action at the beginning and at the ending of the The tinginstruments,and changing'the tightness of knitting and other characteristics 'of thefabric produced. If on the other-hand the necessary operation ofstarting the reel into rotation in eachcycle is performed partly by thepull of the yarns and partly by the power drive of the reel,

controlled by the yarn pull through the pilot member 2|, there stillremains-a degree of disadvantage, at least to the extent that the yarnstend to undergo progressively increasing tension.

. In order to minimize these drawbacks and to oilsetapproximately theprogressive ill effects of the depletion of the yarn, the presentinvention supply, the'rocker 42 and links 45 and 45' op-' end to theupper or free end of an adjuster arm 39. Said arm 39 is shown as mountedon an axle or rockshaf-t 40 located approximately centrally between thefixed axles l5 and I5 of the hubs I6 and Iii of the respective shoelevers. A suinciently strong spring is applied to these parts, forexample pulling rightwardly upon the adluster arm 39, toholdvthefollower 34reliably in contact upon the "supply Y of yarn.

The operation of these partsupon the shoe levers, to relax the brakingfriction of the shoes, is in this instance providedby a short'rocker ortwo-armed lever 42 centrally. mounted on the rockshaft'40. The shoelever hubs l6 andv l6 have horizontal or alined slots 43 and" 43' inwhich are engaged studs 44 and 44'. A link 45 extends from the lower endof the rocker to stud 44 and a similar link 45' fromthe upper end tostud 44'. The hubs lfi'and l6 have a tendency to move apart on theiraxles l5 and I5 by the 1 springs 32 and otherwise so that the studs 44and 44' normally rest at the inner ends of the slots 43 and 43'.Therefore, when the adjuster arm 33 is swung rlghtwardly, with thedepletion of yarn erate so as to allow the hubs to spread or shiftapart. 'This separating action of the. hubs brings about the requiredrelaxing of the friction pressure of the brake shoes on the drum, duringthe gradual depletion of yarn, and independently-of the cyclicaloperation of the brake shoes. Thus, ina sense the shoe levers turn aboutfloating hubs, which initially stand apart to a fixed distance, butwhich gradually are spread further apart during progress of theknitting. By this described arrangement the connections from thefollower 34 to the pressure-relaxing-device 4245 cause the gradualreadjusting of the device so as to reduce the braking pressure andresistance to the rotation of the reel as the yarn thereon becomes usedup.

In operation, the

resistance to the starting up.

of reel rotation in each cycle is presented both by the inertia of theparts to be started and by the frictional resistance of the brake meansor shoes l3 and I3 upon the disk or drum l2 which rotates with the reel.The component of resistonce which is due to the friction of the brakemeans is by this invention reduced progressively to offset approximatelythe increase of resistance due to the lessened radius and leverage ofyarn pull on the reel and the need of an increasing angle of rotation toafford the necessary length of yarn in each cycle. The spreading orshifting apart of the fulcrums of the two friction brake levers isherein utilized as a means of progressively decreasing the frictionalresistance to each advancing movement of the reel. 7 The actual extentof spreading or separating movement of the fulcrums may be quite small,for example of the order indicated by the throw of the spreading rocker42. When the opposite lever hubs are thus caused to move apart, the shoelevers are effectively separated by this progressive adjusting means,independent of cyclical operation of the levers fromtheir other or lowerends. When the upper ends of the shoe levers l4 and 14' are thus shiftedapart, this may relax the pressure of the shoes l3 and I3 themselves,without any need of the shoes leaving contact with the disk l2. In factthe brake shoes preferably have a slotted or equalizing mounting 3| onthe shoe levers as shown, with a pairof springs 32interposed betweeneach lever and shoe; so that the shoes can not move away from frictionalcontact with the. disk, whereas the spreading apart of the leversrelaxes the interposed sprin s 32 and thus decreases the frictionalpressure in the manner and for the purposes already explained.

The second illustrative form of the present invention is shown in Fig.2, taken with the sectional view Fig. 2 of the details of the shoe leverhub piv ting means. As in the first form the follower 34 is on the arm35 swinging about the axle 35 which carries also a rockarm 31 connectedby a link 38 to the fulcrum adjusting devices. There is shown a lefthandadjuster arm 46 and a righthand adjuster arm 43', these being connectedtogether by a cross link 41, the actuating link 38 being also connectedwith this system, being pivoted to the adjuster arm 45. The necessaryresilient bias to hold the follower on the reel is provided by thepulling spring 4|, in this case connected to the adjuster arm 46'.

In this form the shoe arms have floating pivots or hubs provided withoutthe need of loose slot connections as in the first form, the second formproviding, for each of the levers, an axle or fulcrum which is in theform of an eccentric and which therefore needs only to be turned tochange the effective center or axis of swing of the lever. Describingthis device in detail, the adjuster arms 46 and 46' have hubs 48 and 48'within which are eccentric sleeves 49 and 49, these being secured to thehubs'48 and 43' by 'pins 50. The eccentric sleeve in each case extendsthrough and beyond the adjuster arm hub, and is mounted for rotationupon an interior fixed axle or pivot l or IS. The eccentric sleevee'xtensionsare engaged and surrounded by the hubs l5 and iii of the shoelevers I4 and I4. It is therefore clear that as the adjuster arms areswung gradually rightwardly, duringlthe depletion of the yarn, theeccentrics are turned clockwise and thus effect theadjusting shift ofthe fulcrums of the shoe levers as described. The eccentricsarerelatively inverted so as to afford opposite movements to the leverfulcmms, the eccentric 49 thus having its wider side'below the axle l5while the eccentrlc 43" has its wider side above the axle I5;

' wherefore with the gradual exhausting of the gradual spreading apartor separating of the fulcrums of the shoe levers to afford the actionsalready fully described. Y

The third embodiment of the invention,.shown in Fig. 3, while operatingon the same broad principles, differs from the other forms in that theprogressive relaxing of the braking pressure with the depletion of yarnis brought about not by the use of floating fulcrums for the shoelevers, nor by the shifting of those fulcrums, but by a gradualmodification of the resilient or spring force which is the forceutilized to pull together the brake levers and shoes. In thisillustration the progressive adjustment is effected through the crossspring 21 which supplies the main braking force for the cyclical brakingoperation, opposed bythe separating force provided by the swinging pilot2| and the shipper lever l8.

Referring to the specific mechanism shown in Fig. 3 the cross spring}?is shown as having its action modified by a device adjusting one end ofthe spring, rather than by splitting the spring and interposing a devicebetween its two parts. As before, the follower 34 is on a swinging arm35 iulcrumed at 36. In this case the arm 35 is supplemented by a shorterarm 52 extending out,- wardly to the left, thereby to swing upwardlywith the consumption of yarn. Extending from the short rockarm 52 is alink 53 the lower end of which is pivoted to the free outer end of alever 54 which in turn is fulcrumed at 55 upon.

the lefthand brake shoe lever i4. This lever 54 has, beyond its pivot, ashort arm 56, and by a pin 51 or similar mounting the left end of the across spring 21 is secured thereto.

It will be noted that during ordinary operation, through cycle aftercycle, the friction controlling devices cause no interference with thebraking operations, since the shipper l8 can swing apart the shoe leversand the spring 21 can draw them together without hindrance from thefollower connections. However, with the progressive depletion of theyarn the follower arm 35 swings rightwardly or inwardly thus elevatingthe outward arm 52 and the link 53, swinging upwardly the lever 54 andinwardly the short arm 56 thereof, which extends in av generally upwarddirection so that when swung as described it brings about a slightshortening of the spring 21 and thereby a reduction of the spring pulland consequent relaxing of the braking pressure afforded by the spring.It may incidentally be noted that in Fig; 3 the brake-imposing spring 21is mounted by separate adjusting means at its two ends; at its right endthe adjuster 28 is a thumb screw for initial setting of the springtension, while at the left end of the spring its mounting on the leverarm 56 brings about the automatic lessening of the spring tensionthroughout the depletion of the yarn 0n the reel.

The fourth embodiment of the invention, shown in Fig. 4 differsfrom theother three forms in that the progressive relaxing of the brakingpressure during the exhaustion of the yarn from the reel is broughtabout by a gradual readjustthose levers are spread apart during eachknitting cycle to relax the braking action. As before, the shoe lever I4is considerably longer than the'other, so as to accommodate the shipperlever l8 vertically between their ends. The action of the shipper isthat when it is swung by a clockwise turn ofthe axle l9, its upper endacting through an adjustable contact device 60 presses outwardly on theshort shoe lever l4, while a similar contact 6| at the foot of theshipper acts outwardly against the lower end of the shoe lever M. Ineach case the mechanical connection is shown as a thrusting one, so thatthe swinging of the shipper, when the pull of the yarns lowers the pilot2|, causes the thrusting apart of the shoe levers, in each cycle, andtherefore, the relaxing of the braking effect, thus aiding the rotatingof the yarn reel, whether by the pull of the yarns thereon or by a powerdrive mechanism.

In this modification the mechanical relation between the shipper and theshoe levers is utilized as follows. Instead of the shipper contactmembers 60 and iii pressing against contacts that .are mounted fixedlyon the shoe levers, said levers are provided with adjustable contactswhich may be progressively adjusted during the depletion of the yarnto'increase gradually the relaxed condition of the brake levers. In theform shown the contacts on the shoe levers are eccentrics or cams 62 and63 respectively, pivoted respectively by fulcrum pins 64 and 65 on theshoe levers, and having extension arms 66 and 6'! respectively forturning the eccentric contacts to change the adjustments. The two arms66 and 61 are interconnected by a link 68 compelling the two eccentriesto turn through equivalent angles when operated, the eccentrics beingrelatively inverted,

so that when their arms and the link are shifted there will be oppositeand equivalent adjusting actions. When the two eccentric contacts areturned clockwise they operate by reaction against the shipper contactsto thrust apart the shoe levers l4 and [4. By dotted lines the shiftedpositions of the adjusting parts are shown.

It, is the intention that these adjustments shall be effected by changesin the yarn diameter on the reel, as with the other embodiments. vForthis purpose the following additional connections are shown. Extendingoutwardly from the pivot 65 of the eccentric contact 63 is shown arockarm 69 which is connected by a long upright link 10 when anoutwardly projecting arm Ii mounted on the fulcrum 36 which carries thefollower arm previously described, the follower 34 of which bears uponthe yarn supply on the reel. Bv this arrangement, as the yarn isgradually'used up, the inswinging of the follower causes the rise of arm1|, link 10 and arm 69, and this operates through the describedconnections to turn at two eccentric contacts 62 and 63 to change therelations of the shoe levers to the operating shipper, namely, in suchmanner that as the yarn ,is consumed, through cycle after cycle, theadjustable contacts 62 and 63 are shifted in a manner progressively toswing or spread apart the lower ends of the shoe levers, therebyrelaxing the braking force or friction, in the manner already described,so as to facilitate each restarting of the reel and yarn into rotationfor the supplying of yarn to the knitting instruments in each cycle. Asbefore, the force drawing together the shoe levers to apply the brake issupplied by the cross spring 21; and additionally the brake shoes l3 andI3 are caused to maintain continuous frictional contact with thebrakedrum' l2 by means of the local springs 32 providing a resilientthrust between the shoe levers and the shoes floatingly mounted thereon.

In review, in all embodiments an automatic progressive adjustment istion, maintaining substantially steady the yarn tension during itsdepletion and operable from the decreasing diameter of the supply on thereel. Such adjustment is one acting through the frictional braking meanswhich has to be varied during each cycle to permit and then retard thereel rotation; the action hereof being to relax progressively thebraking pressure and friction as the supply diameter grows less, so tooffset the otherwise increasing resistance to each reel-rotatingoperation. The yarn tension is thus kept approximately uniform and thepilot through which the yarn governs the braking action in each cycle iscaused'to have a steady range of swing.

A preferred feature of structure is the springpressed floating mountingof each frictional braking shoe on its lever, ensuring continuousbraking contact of shoe on disk, but yet responding promptly tomovements of the lever as the latter is swung to impose .or relaxbraking action in each cycle; this feature being disclosed in said priorapplication and having utility both with and without the feature ofprogressive relaxing of friction braking pressure during gradualdepletion of yarn'as already herein described.

There have thus been described several illustrative mechanisms embodyingthe principles and attaining the purposes of the invention; but sincemany matters of arrangement, structure, design and operation may bevariously modified without departing from such principles, it is notintended to limit the invention except to the extent set forth in theappended claims:

What is claimed is:

1. In a warp-knitting machine, in combination with a friction brakemeans adapted to stop the feeding rotation of the yarn reel in eachcycle of knitting, a follower bearing movably against the yarn supply onsuch reel and thereby shiftable gradually from an initial outer positiontowards a final inner position as the yarn is consumed, and connectingmeans from the follower to the brake means operable to relax graduallythe degree of braking friction in coordination with the reduction of theyarn supply diameter.

2. In a warp-knitting machine wherein is a brake disk connected torotate with the yarn reel, and a brake shoe .(or a pair) movably mountedto apply retarding effect upon the disk; mechanism for progressivelyreducing the retarding efi'ect of said shoe during the gradual depletionof the supply of yarn on the reel thereby to ease the effort and strainimposed upon the action which occurs during each cycle of acceleratingor starting the yarn and reel into motion; the same comprising a movablefollower arranged to 'bear upon the supply yarn and thus undergoprogressive shifting movement from an initial toward a final positionduring depletion of the yarn, the brake shoe mountings or operatingconnections comprising a device which is operable or adjustable to relaxthe braking pressure independently of the cyclical operation of thebrake shoe, and a connection from said follower to said device such thatwith the progressive shift of the follower the device is adjustedgradually to relax the braking pressure and amount of retarding effectupon the yarn reel.

3. In a warp-knitting machine wherein is a afforded by this inven-'friction brake movably mounted to apply retarding effect upon a brakedisk connected to rotate with the yarn reel; mechanism for progressivelyreducing the friction or retarding effect of said brake during thegradual depletion of thesupply of yarn on the reel thereby to ease theresistance imposed upon the action which occurs during each cycle ofstarting the reel and yarn into motion; the same comprising a movablefollower arranged to bear upon the supply yarn and thus undergoprogressive shifting movement from an initial toward a final positionduring depletion of the yarn, a device associated with the brake andoperable or adjustable to relax the braking pressure independently ofthe cyclical operation of the machine, and a connection from saidfollower to said device such that with the progressive shift of thefollower the device is adjusted gradually to relax the braking pressureand retarding efiect upon the yarn reel approximately in coordinationwith the depletion of the yarn and to offset the tendency to increasedstarting resistance due thereto.

4. In a warp-knitting machine shiftable means controlled in position bythe diameter of the warp supply on the warp beam, the same beingarranged gradually to adjust or diminish the braking'force applied to abrake drum connected to I the warp beam, and thereby substantially toequalize the force required to rotate the warp beam by the pull of theyarn namely in a progressive manner from a full warp beam with a largecircumference and through a decreasing warp circumference, whereby thebraking force is gradually diminished to facilitate the acceleratedrotation of the warp beam in each cycle by the pulling force of theyarn, thereby to provide automatically a substantially equal supply ofyarn through cycle after cycle in the course of knitting the fabric.

5. In a warp-knitting machine a shiftable follower lever controlled inposition by the diameter of the yarn on a warp beam to gradually movethe pivoting points of a pair of brake brackets, and connections linkingsaid lever to an opposite pair of brake-applying levers or brackets,thereby gradually to reduce the spring force applied to the pair ofbrake levers, thus automatically to compensate for the increasingresistance to the pulling force of the yarn as required to afiord asubstantially constant supply of yarn to the knitting elements.

6. A warp-knitting machine wherein are opposed brake levers carryingfriction shoes and with a shipper means to spread apart the shoe leverfree ends in each cycle against the force asoasov 8. A warp-knittingmachine as in claim 6, wherein the adjuster device comprises connectingcontacts between the shipper and the respective shoe lever free ends,the same being adjustable from the follower to spread the leversrelatively to the shipper by reason of the progressive inward shift ofthe follower; and wherein each adjuster device comprises a rotary cam oreccentric contact on its lever, opposed to a contact surface on theshipper.

9. In a warp-knitting machine having a friction brake means comprising ashoe carried on a brake lever or carrier and adapted and operated ineach cycle to apply friction to retard and stop the warp reel rotationand to relax and release the same; in combination with a followerbearing upon the yarn supply upon the reel to shift progressivelyinwardly cycle after cycle as the yarn is depicted, a device associatedwith the brake means adapted to relax the braking pressure and frictionthereof independently of the cyclical operation of the brake means, andconnecting means from the follower to the relaxing device arranged tocause progressively the relaxing of the braking pressure and friction asthe yarn is gradually depleted; thereby to oiiset the tendency togradually increasing resistance to restarting the reel rotation in eachcycle, whereby the yarn tension is maintained approximately uniformthroughout the knitting of the fabric.

10. A warp-knitting machine as in claim 9 and wherein is a resilientlymounted shiftable yarn pilot guide rod having connections for causingthe braking and relaxing of the reel in each cycle, and a longsupporting spring resisting the shift of the pilot rod under the tensionof the yarn.

11. A warp-knitting machine as in claim 9, wherein is a resilientlymounted shiftabie yarn pilot guide rod having connections for causing 40the braking and relaxing of the reel in each cycle,

of resilient means tending to apply the brake, a

follower bearing on the yarn supply on the warp reel thus to undergoprogressive inward shift during depletion of yarn, an adjuster devicebetween the shipper axle and the free ends of the shoe levers, saiddevice being adjustable to vary the spread relation of the shoe leversindependently of cyclical spreading action of the shipper, and

.a connection from the follower to said adjuster device arranged tospread gradually the shoe and a long supporting spring resisting theshift of the pilot rod under the tension of the yarn; and wherein thefriction shoe has a spring mounting on its carrier lever, holding theshoe in continuous frictional engagement; and the shoe lever is springpressed to apply the retarding and stopping action.

12. A warp-knitting machine as in claim 9 and wherein the friction shoehas a spring mounting on its carrier lever, holding the shoe incontinuous frictional engagement; and the shoe lever is spring pressedto apply the retarding and stopping action.

13. In a warp-knitting machine having a friction brake means comprisinga shoe carried on a brake lever and operable in each cycle by moving thelever to impose friction upon a disk thereby to retard and stop the warpreel rotation and thereafter to relax the same for rotation and feed,and means under pilot control from the yarns passing from reel toknitting point arranged to cause in each cycle such imposing andrelaxing action of the brake means; and characterized in that thefriction shoe has a thrusting spring or resilient mounting on its leverwith an action holding the shoe continuously upon the disk, undervariable pressure and friction, as the lever is moved toward and fromthe disk.

14. A warp-knitting machine as in claim 13 and wherein the friction shoehas a slotted floating mountihg upon its lever, and its thrusting springis of such strength and short length as to respond promptly to brakeimposing and relaxing movements of the lever.

15. A warp-knitting machine as in claim 13.

wherein the friction shoe has a slotted floating mounting upon itslever, and its thrusting spring is of such strength and short lengthas'to respond promptly to brake imposing and relaxing movements of thelever; and wherein is a cross spring urging the shoe lever in adirection to impose braking action, and adapted to be overcome by thepilot control to relax the braking action; and the pilot control meanscomprises a long spring which resists the shift of the pilot means underthe tension of the yarn.

16. In a warp-knitting machine having for controlling the yarn feedingmovements of the reel the following: a friction means controlling therotation of the reel and comprising a shoe carried on a lever andoperable in each cycle by moving the lever to impose shoe friction upona drum connected with the reel and thereafter to relax such friction,and means under pilot controi from the yarns passing from reel 'toknitting point and arranged to cause in each cycle such frictionimposing and relaxing action; and characterized in that the frictionshoe is carried on its lever by a thrusting spring or resilient mountingwith an action holding the shoe continuously upon the drum, undervariable pressure and friction, as the lever is moved toward and fromthe disk.

1'7. A warp-knitting machine as in claim 13 and wherein is a crossspring urging the shoe lever in a direction to impose braking action,and adapted to be overcome by the pilot control to relax the brakingaction; and the pilot control means comprises a long spring whichresists the shift of the pilot means under the tension of the yarn.

18. In a warp-knitting machine wherein is a friction brake shoe movablymounted to apply retarding effect upon a brake disk connected to rotatewith the yarn reel; mechanism for progressively reducing the friction orretarding effect of said brake during the gradual depletion of thesupply of yarn on the reel; the same comprising a movable followerarranged to bear upon the supply yarn and thus undergo progressiveshifting movement from an initial toward a final position duringdepletion of the yarn, a device associated with the brake and operableor adjustable to relax the braking pressure independently of thecyclical operation of the machine, and'a con nection from said followerto said device such that with the progressive shift of the follower thedevice is adjusted gradually to relax the brak-- ing pressure andretarding effect upon the yarn reel approximately in coordination withthe depletion of the yarn; said mechanism being fur-- ther characterizedin the provision of a lever carrying the brake shoe. said shoe leverhaving its fulcrum adjustably shiftable to vary the braking pressure ofthe shoe, and the connections from the follower operating to shift suchlever fulcrum progressively to relax the braking pressure with thegradual depletion of yarn.

19. A warp-knitting machine as in claim 18 and wherein is an opposedpair of shoes with a carrying lever for each, and a rocker adapted tocause shift outwardly of each shoe lever fulcrum,

the connections from the follower operating to turn the rocker andthereby shift the fulcrums.

20. A warp-knitting machine as in claim 18 and wherein is an opposedpair of shoes with a carrying lever for each, and a cam adapted tothrust outwardly each,shoe lever fulcrum, the connections from thefollower operating to turn the cam and thereby shift the fulcrums; and

axle.

21. A warp-knitting machine as in claim 18 and wherein is an opposedpair of shoes with a carrying lever for each, and each shoe lever hubturns upon an eccentric as a fulcrum, and the connections from thefollower operate to turn the eccentric and thereby adjust the axis ofswing of the lever. I

22. In a warp-knitting machine wherein is a friction brake having.opposed shoes movably mounted to apply retarding effect upon a brakedisk connected to rotate with the yarn reel; mechanism for progressivelyreducing the friction or retarding effect of said brake during thegradual depletion of the supply of yarn on the reel; the same comprisinga movable follower arranged to bear upon the supply yarnand thus undergoprogressive shifting movement from an initial toward a final positionduring depletion of the yarn, a device associated with the brake andoperable or adjustable to relax the braking pressure independently ofthe cyclicaloperation of the machine, and a connection from said folingtheir fulcrums adjustable to vary the braking pressure of the shoes, andthe connections from the follower operating to adjust apart said leverfulcrums progressively to relax the braking pressure in coordinationwith the gradual depletion of the yarn.

23. A warp-knitting machine as in claim .22 and wherein is a rockeradapted to cause shift outwardly of each shoe lever fulcrum, theconnections from the follower operating to turn the rocker and therebyshift the fulcrum.

24. A warp-knitting machine as in claim 22 and wherein is a cam adaptedto thrust outwardly each shoe lever fulcrum, the connections from thefollower operating to turn the cam and thereby shift the fulcrums; andeach shoe lever fulcrum comprising a slotted floating hub rotatable andshiftable upon a fixed axle.

25. A warp-knitting machine as in claim 22 and wherein each shoe leverhub turns upon an eccentric as a fulcrum, and the connections from thefollower operate to turn the eccentric and thereby adjust the axis ofswing of the lever.

26. Warp-knitting machine as in claim 22and wherein each shoe lever hubturns upon an eccentric as a fulcrum, and the connections. from thefollower operate to turn the eccentric and thereby adjust the axis ofswing of the lever; the two eccentrics being relatively inverted, eachwith an upstanding adjuster arm, and said arms being link-connected witheach other and the follower.

27. In a warp-knitting machine wherein is a friction brake means havingshoes movably mounted to apply retarding effect upon a brake diskconnected to rotate with the yarn reel; mechanism for progressivelyreducing the friction or retarding effect of said brake during thegradual depletion of the supply of yarn on the reel; the same comprisinga movable follower arranged to bear upon the supply yarn and thusundergo progressive shifting movement from an initial toward a iinalposition during depletion of the yarn. a device associated with thebrake and operable or adjustable to relax the braking pressureindependently of the cyclical operation of the machine, and a connectionfrom said follower to said device such that with the progressive shiftof the follower the device is adjusted gradually to relax the brakingpressure and retarding effect upon the yarn reel approximately incoordination with the depletion of the yarn; said mechanism beingcharacterized further in the provision of opposed brake shoe leverscarrying the friction shoes, with means operating on the free ends ofthe levers to vary the braking action in each knitting cycle, and atension pull spring extending across from lever to lever and'providingthe frictional pressure for the brake shoes, said cross spring having adevice for adjusting its tension, and a connection from the follower tosaid device adapted to operate said device to reduce the tension of thespring progressively with the depletion of the yarn.

28. A warp-knitting machine as in claim 27 and wherein said devicecomprises a swingable mounting for one end of the spring upon one shoelever.

29. A warp-knitting machine as in claim 2'1 and wherein said devicecomprises a swingable mounting for one end of the spring upon one shoelever and a manual tension adjusting means on the other lever.

30. A warp-knitting machine as in claim 16 and wherein the frictionmeans is a friction brake device for retarding the reel, and comprises adrum and a pair of shoes bearing thereon and levers carrying the shoes,with spring mounting means between levers and shoes causing continuousfriction engagement of the shoes upon the drum throughout the feedingperiod of each cycle.

31. In a warp-knitting machine having for controlling the yarn feedingmovements of the reel the following: a friction means controlling therotation of the reel and comprising a shoe carried on a lever andoperable in each cycle by moving the lever to impose shoe friction upona drum connected with the reel, thereby to retard the reel, andthereafter to relax such friction, and means under pilot control fromthe yarns passing from reel to knitting point and arranged to cause ineach cycle such friction imposing and relaxing action; the friction shoebeing carried on its lever by a resilient mounting with an actionholding the shoe continuously upon the drum, under variable pressure andfriction, as the lever is moved toward and from the disk; andcharacterized further in the provision of a means responsive to theprogressive depletion of the yarn on the reel and connected to adjustprogressively the friction imposingand relaxing action for reducinggradually the reel retarding effect as the yarn under-

